Posthole digger attachment for tractors



Sept. 1 1, 1945.

R. J. PIPER POSTHOLE BIGGER ATTACHMENT FOR TRACTORS Filed June 26, 19442 SheetsSheet 1 Wk 1, 0 e)" aim/ 1 er a 9' Filed June 26, 1944 2Sheets-Sheet 2 ,Qop er We per g M MW; TT

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Patented Sept. 11, 1945 POSTHOLE BIGGER ATTACHDIENT FOB TRAC'EOBS RogerJune Piper, Princeton, El. Application .iune 26, 1944, Serial No.542,097

3 Claims.

The present invention pertains to a novel posthole digger attachment fortractors and constitutes in many respects an improvement upon that shownin my prior Patent No. 2,250,081, issued July 22, 1941.

One object of the present invention is to provide such an attachmentembodying a novel arrangement for manually applying torsion either tospeed up or retard the feed of the auger to accommodate particularground conditions which may be encountered.

More specifically, it is an object of the invention to provide anattachment of the character indicated embodying a novel arrangementutilizing a single operating shaft for not only applying force. eitherto speed up or retard the feed of the auger bit, but also to adjust theangle of tilt of the auger with reference to the tractor, such shaftbeing conveniently manipulable from the drivers station that may besomewhat remote from the auger (for example, the drivers station may beat the rear of the tractor and the auger itself mounted on the oppositeor front end), thus making possible one man operation of the wholeoutfit.

Further objects and advantages of the invention will become apparent asthe following description proceeds, taken in connection with theaccompanying drawings, in which Figure 1 is a perspective View of aposthole digging attachment embodying the present invention and shown asapplied to a tractor, the latter being indicated in dotted outline.

Fig. 1 is an enlarged detailed sectional view taken substantially alongthe line l-l in Fig. i.

Fig. 2 is a view similar to Fig. l, on a somewhat smaller scale, andshowing the attachment adjusted for boring with the tractor stationedonahillside.

Fig. 3 is a plan view of the attachment, partially in section along theline 33 in Fig. 1.

Fig. 4 is an enlarged fragmentary detailed view of a portion of theoperating shaft or the attachment.

Fig. 5 is a iragmentary vertical sectional view through the upperportion of the supporting housing of the attachment.

Fig. 6 is a vertical sectional view taken substantially along the line6-6 in Fig. 3. 7

While the invention is susceptible of various modifications andalternative constructions I have shown in the drawings and will hereindescribe in detail the preferred embodiment, but it is to he understoodthat I do not thereby intend to limit the invention to the specific formdisclosed, but intend to cover all modifications and alternativeconstructions falling within the spirit and scope of the invention asexpressed in the appended claims.

Referring more particularly to the drawings, the invention has beenexemplified therein as embodied in a posthole digging attachment appliedto a tractor T and from which it is powered. The tractor itself may, ofcourse, be of conventional form and it is, in fact, one of the virtuesof the present attachment that it is applicable to a wide variety oftractors. The tractor T here shown has, as is common, a power take-offpulley Ill on one side and a drivers station at the rear end where theseat H and steering wheel is are located.

In the present instance, the attachment is shown as secured to the endof the tractor opgp posite the drivers seat, that is to say, at thefront end. For that purpose it embodies a reinforced mounting frame Itof generally U-shape (see Fig. 3), the arms M or which embrace the frontend of the tractor and are detachably bolted to the chassis, asindicated at l5.

On the side or the frame is opposite the power take-0E is an uprightsupporting housing It of tubular form with a gear housing H at its lowerend portion constituting, in efiect, an enlargement of the same. Anauger drive shaft l8 extends axially upward within this housing andprotrudes from its lower end with an auger Ibit l9 fixed theretosuitable dor boring in the earth. To support the housing structure 16,ll on the frame M for tilting motion with reference to the tractor, thesame is, in the present instance, pivoted by means of a sleeve 20 rigidwith the gear housing H and projecting laterally from such housingtransversely across the frame (see Figs. 3 and 6). This sleeve isjournaled in bearings 2i fixed to the frame so that the housingstructure 16, ll carrying the auger may tilt fore and aft of the tractorabout the horizontal axis of the sleeve 25.

The auger shaft I8 is journaled within the housing structure It, I! forboth rotational and endwise movement. For that purpose the shaft l8,which is of square cross section, is slidaoly received within a sleeve22 (Fig. 6) joumaled within the gear housing l1 and restrained against.

axial movement with reference to the latter. The axial opening withinthe sleeve, through which the shaft l8 projects, is of complementalsquare cross section so that the shaft and sleeve turn .58- together.although the shaft is slidable endwlse with reference to the sleeve. Thedrive conthe power take-off pulley l includes the sleeve Thus a bevelgear 23 is fixed to this sleeve 22. and meshes with a pinion 24 on theadjacent end of a shaft 25 which extends axially through the housingsleeve 20. Fixed on the opposite end of this shaft 25 is 'a pulley 26connected in driven relation with the power take-off pulley It by anendless belt 21. It will thus be seen that the auger supporting housingi8, I! may be freely tilted about the axis of the sleeve and shaftwithout impairing the drive connection from the power take-off.

The feed of the auger into the ground is normally accomplished by thelead of its bit l8. Various soil conditions may, however, necessitateapplication of force either in a downward direc tion to augment the rateof feed, or in an upward direction to retard the feed. For example, inboring in very hard ground, it may be necessary to push down on theauger to get it to feed properly, whereas in soft wet ground it may benecessary to restrain the auger against feeding too fast in order tokeep it from becoming clogged with earth. Moreover, provision mustIbemade for applying force to the auger to lift it from the hole afterboring is completed.

To accommodate manual application of force to the auger shaft in anendwise direction for the various purposes indicated, and with a minimumof muscular effort, a pair of chain-connected and suitably ratioedsprockets 28, 23 is used (Figs. 1 and 5). A ratio of'high mechanicalad-, vantage is afforded by making the number of teeth on the sprocket28 but a minor fraction of that on the sprocket 2-8, in the presentinstance the ratio being one to three. An endless chain 30 connectsthese sprockets. The lower sprocket 28 is fixed on a stub shaft 3|journaled in a bushing 32 rigid with a split sleeve clamp 33. The latterembraces the housing l8 and may be adjusted longitudinally of the latterto tension the chain 30.

The upper sprocket 29 is fixed to a stub shaft 29 (Fig. 5) journaled ina bearing provided on a cap 34 forming a closure for the top of thehousing l6. Also fixed on the shaft 33 is a pinion 35 meshing with arack 36 for converting rotary motion ofthe sprocket 29 into translatorymotion. The rack 36 passes through a rectangular aperture 31 in the cap34 and is thus restrained against rotation, the lower end of the rack 36being connected by a thrust bearing 38 with the upper end of the augershaft IS. The external diameter of the latter is such as to telescopewithin the housing l6 and guide the upper end of the auger shaft. Theshaft l8 and rack 36 thus move endwise in unison, the shaft beingpermitted to-rotate while the rack is restrained against rotation.

To make possible one-man operation of the tractor and attachment fromthe driver's seat -II at the rear of the tractor, provision has beenmade for not only revolving the sprocket 23 from that, point, but alsofor adjustably tilting the auger in a fore-and-aft direction. .A singleop erating shaft, designated generally as 33, is used for performingsuch dual functions. Torque applied manually by the driver istransmitted through such shaft to the sprocket 23, and the shaft itselfis adjustably shortened or lengthened to tilt the auger. In the presentinstance the shaft 33 includes a rod 40. connected at one end byuniversal joint 4| with the sprocket 23,

and of square cross section in order that its opposite end may betelescopically received within a square sleeve 42 (see Fig, 4). Rigidwith the opposite end of the sleeve 42 is a round rod or shaft 43rotatably Journaled in a sleeve 44 and restrained against endwisemovement relative to the latter by suitable inwardly facing shoulders orcollars 44- on the shaft 43 abutting the ends lof the sleeve 44 (seeFig. 1 The bearing sleeve 44 is fixed to an upright 44" which may bedetachably secured to the tractor in any convenient manner, as, forexample, by clamping the same to a supporting strut for the steeringcolumn. Coupling of the telescoping operating shaft members 40 and 42 toaccommodate relative axial adjustment of the same for lengthening orshortening the operating shaft is accomplished through the use of a bar45 (see Fig 4) slotted longitudinally, as indicated at 46. The forwardend of this bar is fixed to a stud 41 rigid with the upper one of a pairof transverse straps 48 tightly clamped to the bar 40 by bolts 49, Theopposite end of the bar 45 has on it a laterally projecting hand grip 50which may be conveniently grasped by the operator to either pull thesame toward him or shove it away from him and respectively shorten orlengthen the operating shaft 39. The slotted bar 45 is clamped in itsselected adjusted position by a clamping n-ut 5i having a hand grip 5iand threaded on a stud 52 passing through the slot 46, such stud beingrigid with the upper one of a pair of straps 53 tightly clamped to thesleeve 42 by bolts 54. For rotation of the operating shaft 38 a pair ofoperating handles 65 (Fig. 1) are provided at opposite ends of atransverse bar 56 rigid :with the end of the shaft 42, the bar -58 beingfairly long so as to give a leverage of high mechanical advantage forapplying torque to the shaft 39 with minimum muscular effort.

The operation of the tractor attachment will. in general, be clear fromthe foregoing. By way of recapitulation, it may be assumed that thetractor T has been stopped with the auger bit 19 located verticallyabove the point at which it is desired to bore a hole. 'Ihereupon thedriver engagesthe drive to the power take-off pulley Ill from thetractor engine, as, for example, through use of the conventional controllever 51, thus initiating rotation of the auger. The latter is loweredby turning the operating shaft 39 until it begins to bite into theground. As the boring operation proceeds the driver observes the sameand either retards or augments the axial feed of' either to thrust theauger downward or restrain its downward movement, as may be required. AtI the completion of the boring operation the power take-off drive isstopped, thus stopping rotation of the auger, and the operating shaft 38turned manualy to raise the auger bit and thus withdraw it from thehole. Because of the mechanical advantage afforded by the leverage ofthe operating handle mechanism 55, 56 and the ratio of the sprockets 28,29, comparatively little muscular effort need be exerted in eithercontrolling the rate of auger feed or withdrawing the same;

After completing the boring of a hole as described, the driver reachesforward, loosens the clamping nut 5|, and moves the slotted bar 4'endwise to tilt the housing It and anger carried thereby so that thelatter is cleared from the position, as, for example, on a slope, asindi-' cated in Fig. 2.

From the foregoing it will be seen that a simple and rugged postholedigger for tractors has been provided. Moreover the same may be readilymanipulated by a tractor driver for full control of the boring operationand the angle of the hole bored without the necessity of his leaving hisnormal operating station on the tractor. A series of holes may thus bebored with great rapidity.

I claim as my invention:

1. In a posthole digging attachment for tractors, the combination of anearth auger depending from the lower end of an upright shaft and adaptedto be driven from a power take-o8 on the tractor, a support journalingsaid auger shaft for both rotational and endwise movement, means fordetachably mounting said support on the tractor for tilting motion abouta point displaced from the drivers station, a second support adapted tobe mounted adjacent the drivers station, an elongated operating shaftextending between said supports and including a pair of members slidablyadjustable axially of each other to alter the length of such shaft, oneof said shaft members being journaled on said second support andrestrained against endwise movement with respect to it, a manualoperating handle on said operating shaft adjacent the drivers stationadapted for use in rotating said shaft to transmit torque through thelatter, and means including a rotary member journaled on thefirst-mentioned support and attached to the adjacent end of saidoperating shaft for utilizing torque applied to said operating shaft toimpart an endwise thrust to said auger shaft, adjustment in the lengthof said operating shaft serving to adjust the angle of tilt of saidfirst-mentioned support and the auger carried thereby about said pivotpoint.

2. In a posthole di ging attachment for tractors, the combination of anearth auger depending from the lower end of an upright shaft and adaptedto be driven from a power take-oi! on 55 tilt said the tractor, asupport journaling said auger shaft for both rotational and endwisemovement,

means for detachably mounting said support on the tractor for tiltingmotion about a pivot point displaced from the drivers station, a secondsupport adapted to be mounted adjacent the drivers station, anextensible operating shaft extending between said supports and includinga pair of telescoping members, a longitudinally slotted bar rigid withone of said members and a. stud on the other member projecting throughthe slot in said bar, a laterally projecting hand grip on 1 housing, apinion meshing with said rack and having a toothed sprocket rotatabltherewith,

said bar for moving the same endwise to adjust the length or saidextensible operating shaft, means for releasably clamping said stud atany selected point along the length of said slot, means i'or iournalingone of said shaft members on said second support, and means including arotary member ioumaled on the first-mentionedsupport and attached to theother of said shaft members for utilizing torque applied to saidoperating shaft to impart an endwise thrust to said auger shaft.

3. in a posthole digging attachment for tractors, the combination of anearth auger depending from the lower end of an upright shaft and adaptedto be driven from a power take-oi! on the tractor, an upright generallytubular supporting housing in which said auger shaft is journaled forboth rotational and endwise movement, means for detachably mounting saidhousing on the front end of the tractor chassis for tilting motion in adirection generally ior and aft of the tractor, a rack connected to theupper end of said auger shaft to move endwise therewith and restrainedagainst rotation within said a second toothed sprocket, the number ofteeth on the latter being but a minor fraction of the number of teeth onthe first-mentioned sprocket, said sprockets being connected by anendless chain, a support adapted to be mounted adjacent the driversstation at the rear end of the tractor,

an elongated operating shaft adapted to extend from front to rear of thetractor and including a pair of members siidably adjustable axially ofeach other to alter the length of such shaft, one

of said shai't members being journaled on said I support and having amanual operating handle thereon for rotating the shaft. and means including a universal joint for connecting said second "sprocket to theforward end of said operating shait for rotation by the latter andadjustment in the length or said operating shaft serving to housingabout said pivot point.

ROGER JUNE PIPER.

